(1) Field of the Invention
This invention relates to an anchor mounting device suitable for use in vehicle seat belts, and more particularly to an adjustable anchor mounting device for 3-point support type vehicle seat belts.
(2) Description of the Prior Art
Coupled with the current trend toward faster vehicles, there is an ever-increasing need for wearing seat belts in order to protect occupants safely on emergencies such as collisions, sudden stops, etc. It is general to adopt a 3-point support type seat belt so as to simultaneously restrain the occupant's torso and lap area from the viewpoint of avoiding any secondary collision against interior structural parts of the vehicle.
Since the physical constitution of each occupant who wears a seat belt is different to a considerable extent, there was a danger that the occupant would not be effectively protected in case of emergency if the position of the anchorage for the shoulder webbing, which restrained the torso, was either too high or too low. This is true because the webbing extends over the face or neck area of the occupant in the former case and, in the latter case, does not come to the shoulder area but passes over the arm.
As countermeasures to the above problem, there have been proposed some anchor mounting devices which permit to attach their anchor plates at two or more locations so as to allow the occupants to select optimum locations for the attachment of the anchor plates depending on their physical constitutions. Reference may be made to U.K. Patent Specification No., 2,078,092A naming P. A. Rentrop Hubbert & Wagner and Fahrzeugausstattungen GmbH & Co. KG. as joint applicants and French Patent Specification No. 81 06624 naming Keiper Automobiltechnik GmbH & Co., KG as its applicant. However, there seems to be still some room for improvement to such anchor mounting devices because some of such anchor mounting devices require extremely irksome operations for positional adjustment of their anchor plates, other anchor mounting devices are unable to maintain their locations of attachment without failure or some other anchor mounting devices have complex structures.